[16.25] Search for Unpredicted Gamma-ray Lines with INTEGRAL/SPI

K. Watanabe (UMD/NASA/GSFC), B. Teegarden (NASA/GSFC)

ESA's INTEGRAL mission was launched in October, 2002. The
on-board Spectrometer SPI is the most sensitive high
resolution gamma-ray spectrometer thus far flown in space.
We have undertaken a global search of the SPI data for
unpredicted gamma-ray lines. Photon counts in each detector
are summed per pointing. We analyze the summed spectra with
software we developed. We identify some lines due to
isotopes with long half-life times, and radiation damage of
the space craft. We realize that imperfect gain corrections
cause some difficulties for this study in high energy (> ~ 4
MeV). We also point out that minor solar flares are sources
of strong lines such as the 4.4 MeV Carbon line. We report
preliminary upper limits on temporally and spatially
varying gamma-ray line fluxes.